[Info-vax] Long uptime cut short by Hurricane Sandy

[David Froble]

Stephen Hoffman wrote:
> On 2013-01-31 14:13:55 +0000,   VAXman-  @SendSpamHere.ORG said:
> 
>> Show me... without PIPES and myriad other *IX utilities.  Compare only 
>> /bin/bash scripting semantics with DCL's.
> 
> Um, why?  I've already indicated that the bash shell syntax is cryptic.
> 
> I haven't written very many bash scripts without using at least some of 
> the Unix utilities, or without using pipes.  I also haven't written very 
> many DCL procedures that would meet the same requirements, as most 
> common DCL commands are external to the DCL CLI, and I'm finding PIPE 
> quite useful in a number of procedures.
> 
> If there's a discussion of syntax, I've already granted that bash is 
> more cryptic than DCL.  Far more.  Yes, DCL has its share of cryptic 
> syntax, too.  This starting with the quoting, and the two-pass 
> substitution using apostrophes and ampersand, and particularly when 
> mixing quotes and apostrophe and ampersand and PIPE, and when quoting 
> substitutions.  Is DCL a paragon of clarity?  No.   But is this DCL as 
> cryptic as bash?  No.  Nowhere near.
> 
> While the following technically violates the requirements, here's a 
> simple bash construct that's very handy:
> 
> filename=$filenameprefix"_`date +%Y%m%d%H%M%S`.dmp"
> 
> For those unfamiliar with bash, this invokes the date command — one of 
> those myriad Unix utilities — in-line and loads a sortable date and time 
> directly into the filename specification.
> 
> Can you perform the same sequence entirely in DCL using lexical 
> functions?  Sure.  Bash and DCL are both Turing Complete, so you can do 
> most anything you need[1].  Here's the DCL version of the previous 
> example, and this version avoids calling out[2] to external executables:
> 
> $ filename = filenameprefix + "_" + f$cvtime(,,"YEAR") + 
> f$cvtime(,,"MONTH") + f$cvtime(,,"DAY") + f$cvtime(,,"HOUR") + 
> f$cvtime(,,"MINUTE") + f$cvtime(,,"SECOND") + ".dmp"
> 
> I've written this DCL many times, as has VAXman, as have many other folks.

Yes, I have, and my comment is that when I'm reading the above, I easily 
get the idea that f$cvtime is doing something with dates, and "MONTH", 
"DAY" and such gives me an idea without thinking about the details of 
what's being worked with.

Now in the bash example, I have to admit that "date" is a bit of an 
indicator, and with some thinking I should realize what "Y", "m", "d", 
"H", "M", and "S" might be referring to, I don't have a clue why some 
are uppercase and some lowercase, or if it matters.

I've always felt that any code written should be easy to maintain, and 
DCL being a bit more verbose and "english" provides a lot of that.

And yeah, it can entail more typing ...